Damper construction

ABSTRACT

A damper construction for a convection heat exchanger in which the effective opening of a hot air outlet slot can be varied by rotating a cylindrically curved damper element that extends lengthwise with the slot and cooperates with adjacent wall surfaces to establish laminar air flow for improved heat output.

United States Patent 1191 Wenig 5] Apr. 16, 1974 [5 DAMPER CONSTRUCTION 3,447,597 6/1969 McNabney l65/55 2,656,781 1019 11 [76] Inventor Norma wenig 39 Hammer 3,375,773 4196; 366261166 et al. di 13i)? Scarsdale, NY 10583 3,139,020 6/1964 Schemenauer 165 96 x [22] Filed: Apr. 18, 1972 Appl. No.: 245,101

References Cited UNITED STATES PATENTS l/l959 Leigh 98/40 C Primary Examiner-Albert W. Davis, Jr. Assistant ExaminerS. J. Richter [5 7] ABSTRACT A damper. construction for a convection heat exchanger in which the effective opening of a hot air outlet slot can be varied by rotating a cylindrically curved damper element that extends lengthwise with the slot and cooperates with adjacent wall surfaces to establish laminar air flow for improved heat output.

4 Claims, 4 Drawing Figures PATENTED R 15 I974 SHEET 2 UF 2 FIG. 4.

FIG. 2.

DAMPER CONSTRUCTION BACKGROUND AND SUMMARY OF THE INVENTION The present invention relates in general to convection heat exchangers, and more particularly to a damper construction for a convection heat exchanger of the type having walls that define an air flow path from an inlet to an elongated outlet slot.

Such heat exchangers are commonly used as baseboard radiators in homes and commercial buildings, and typically contain finned tubes through which hot water circulates. There exists a need for controlling the hot air output of such heaters, and in the prior art such need has been fulfilled by long vane typedampers that are pivotally connected to brackets spaced along the heater wall. Because there were a multiplicity of pivot connections, and the pivot friction had to be sufficient to prevent the vane from falling into a closed position of its own weight, it was frequently difficult to set such vane damper at a uniform setting along its entire length. Furthermore, the pivot connections were vulnerable to jamming by paint and corrosion.

The invention eliminates such problems of damper sticking by providing a construction in which there are no pivot connections to the damper element. According to a preferred embodiment of the invent-ion there are provided a plurality of brackets connected to the back wall of the heat exchanger at locations spaced along the length of the outlet slot. An elongated, cylindrically curved damper element is disposed in sliding contact engagement with the brackets for support thereby and for movement relative to the outlet slot to selectively vary the effective opening thereof and thereby correspondingly adjust the air flow exiting through the slot.

The cylindrically curved damper element cooperates with adjacent wall surfaces of the heat exchanger to establish laminar air flow for improved heat output.

Stop parts located on the brackets, and/or the heat exchanger wall are arranged to bear against corresponding parts of the damper element and thereby limit the travel thereof at preselected fully open and fully closed positions.

As contemplated by the invention, the damper element can be supported by bearing surfaces or edges of the brackets which contact the outside curved surface of the damper, or by bearing surfaces, edges or rollers carried by the brackets and which contact the inside curved surface of the damper.

For a better understanding of the invention, and its various advantages, reference should be had to the following detailed description and accompanying drawing which exemplify certain preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 is a perspective view of a baseboard heater equipped with a damper construction according to a preferred embodiment of the invention, and with the front cover wall of the heater shown in phantom to reveal the internal structure.

FIG. 2 is an elevation section view of the baseboard heater shown in FIG. 1 as taken along line 22 therein.

FIG. 3 is an elevation section view, similar to FIG. 2,

' of a baseboard heater equipped with a damper construction according to another embodiment of the invention, and

FIG. 4 is an elevation sect-ion view, similar to FIGS.-

2 and 3, of a baseboard heater equipped with a damper construction according to a further embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION In FIGS. 1 and 2 there is shown a convection heat ex,- changer in the form of a modular length baseboard 'heater unit whichin practice is connected end-toand abuts against the floor 16.

Within unit 10 is a length of finned tube 17 supported by brackets 18 connected to wall 11. Hot water is ordinarily circulated through tube 17 by suitable conventional plumbing connections at the ends thereof (not shown). Such hot water circulation produces a natural circulation convection heating effect whereby air en ters through inlet 13, is heated as it rises, sweeping across the finned tube 17 and exits through outlet slot 14.

As is well known, the heat output of unit 10 can be adjusted by changing the air flow volume that sweeps of slot 14. Damper 19 is cylindrically curved and ex-' tends for approximately the full length of slot 14.

Brackets 20 each have a pivotally adjustable contact member 21 disposed for sliding contact engagement with the inside surface of damper 19. The contact members 21 are adjusted about their respective pivot connections 22 sothat the outside, convex surface of damper 19 is in sliding contact engagement with the back wall 11 and passes in close proximityto the lip 32 of the upper bent portion 31 of wall 11. If desired, the outside of damper 19 can be positioned so as to wipe against lip 32. With either of these arrangements, the damper l9 cooperates with adjacent wall surfaces 11, 31, 32 to establish a streamlined change in the direction of the air flow path in the vicinity of outlet slot 14 with the effect that the exiting heated air has laminar flow, thereby giving improved heat output.

To selectively vary the effective opening ofoutlet slot 14, and thereby correspondingly adjust the air flow exiting therethrough, damper 19 is moved slidably relative to outlet slot 14, in the direction indicated by the arrow X to decrease the air flow, and in the reverse direction to increase it. The cross sectional arcuate length of damper 19 is chosen in relation to the size of outlet slot 14 to allow complete closure thereof. To accommodate manual movement of the damper 19 there are connected thereto handles 23 positioned for exposure through outlet slot 14.

In accordance with the invention, the movement of damper 19 is limited such that it can travel between a position in which outlet slot 14 is fully open,-and a position in which damper l9 completely obstructs the slot 14. On each bracket 20 there is provided an edge portion 24 located so as to bear against the forward edge 3 25 of a lip 33 extending lengthwise on damper 19, and thereby stop further movement thereof beyond the -fully closed position. Movement of damper 19 in the in FIG. 3 there is exemplified a baseboard heater A which is substantially the same as the heater 10 except that instead of using a contact member 21 in sliding contact with the damper 19, each bracket A has a pivotally connected adjustable arm 21A to which is connected a roller 30 disposed for rolling contact engagement with the damper 19 to support same.

In FIG. 4 there is exemplified a baseboard heater 108 which is generally similar to the heaters 10 and 10A except that the damper 19 is supported by a type of bracket 40 which has an arcuate edge 41 in bearing contact engagement with the outside curved surface of damper 19.

Regardless of whether the damper 19 rests of its own weight upon edges 41, or is supported on the inside as by contact members 21 or rollers 30, the friction be tween damper 19 and the stationary parts which contact it, is sufficient to hold damper 19 in whatever open or closed setting it is put at, without the friction being so high that parts of damper l9 bind and twist when it is turned by pushing at any point along the length of the damper 19. It has been found that a damper 19 made of plastic gives satisfactory friction properties.

From the foregoing, it can be appreciated that the invention can be modified, in ways that will become obvious to the artisan, in order to meet the needs of a particular application. While the invention has been described in connection with natural circulation convection heaters, it is also applicable to other types of heaters as well as air conditioning systems.

What is claimed is:

1. In a natural convection heat exchanger having a front wall and a back wall extending in elevation to define an air flow path from a lower inlet to an elongated upper outlet slot, a damper construction which comprises a plurality of brackets connected to one of said walls and disposed at respective locations spaced along the length of said outlet slot, and an elongated cylindrically curved damper element supported by said brackets for sliding movement relative thereto and relative to said outlet slot to selectively vary the effective opening thereof and thereby correspondingly adjust the air flow exiting through said slot, said brackets having respective parts disposed for underlying sliding contact engagement with said damper element to provide underlying support therefor, said damper element being positioned in generally tangential relation to a flat surface of said back wall to cooperate therewith to establish a streamlined change in the direction of said air flow path.

2. A damper construction according to claim 1 wherein said brackets each have an adjustable contact member disposed for sliding contact engagement with said damper element.

3. A damper construction according to claim 1 including stop parts disposed for engagement with said damper element tov limit the movement thereof between a position in which said slot is fully open and a position in which the damper completely obstructs the slot.

4. A damper construction according to claim 1 wherein said damper element has a lip disposed to accommodate manual movement of the damper element and disposed to engage a wall surface of the heat exchanger to limit the movement of the damper element relative to said slot. 

1. In a natural convection heat exchanger having a front wall and a back wall extending in elevation to define an air flow path from a lower inlet to an elongated upper outlet slot, a damper construction which comprises a plurality of brackets connected to one of said walls and disposed at respective locations spaced along the length of said outlet slot, and an elongated cylindrically curved damper element supported by said brackets for sliding movement relative thereto and relative to said outlet slot to selectively vary the effective opening thereof and thereby correspondingly adjust the air flow exiting through said slot, said brackets having respective parts disposed for underlying sliding contact engagement with said damper element to provide underlying support therefor, said damper element being positioned in generally tangential relation to a flat surface of said back wall to cooperate therewith to establish a streamlined change in the direction of said air flow path.
 2. A damper construction according to claim 1 wherein said brackets each have an adjustable contact member disposed for sliding contact engagement with said damper element.
 3. A damper construction according to claim 1 including stop parts disposed for engagement with said damper element to limit the movement thereof between a position in which said slot is fully open and a position in which the damper completely obstructs the slot.
 4. A damper construction according to claim 1 wherein said damper element has a lip disposed to accommodate manual movement of the damper element and disposed to engage a wall surface of the heat exchanger to limit the movement of the damper element relative to said slot. 